Blistering of the skin typically is caused by some type of trauma. One example of such trauma is friction between an item of clothing or a shoe, and the skin surface beneath the clothing or shoe. Another example of such trauma is scalding or burning of the skin by a heated or cold object or fluid. Blisters may form as a result of, for example, a second-degree burn caused by scalding water or gas, or contact with a hot surface. Another example of trauma is an infection or disease such as pemphigus. Such trauma causes fluid to collect in a blister structure either under the epidermis or within the epidermis. This fluid is sterile, and protects the underlying dermal layer from pathogens. Preferably, the blister structure should be prevented from popping until healing has occurred to maintain protection of the underlying dermal layer. Once healing has occurred, the fluid within the blister is reabsorbed into the body, and the overlying, dead tissue may either fall away or, if necessary, be debrided. Regardless of the cause of the blister, a blister may be popped as a result of frictional forces that bear on the blister, puncture from a sharp instrument or the application of pressure to the blister.
Typically, blisters or wounds are covered with bandages or the like to prevent direct frictional contact between clothing or other surfaces and the blister or wound, or to prevent sharp instruments from puncturing the blister. Such conventional bandages generally include a sterilized pad centrally mounted on a relatively larger adhesive strip such that the adhesive strip extends past the sterilized pad on either side, or all around the perimeter thereof. When the sterilized pad is placed over a blister, the extended portion of the adhesive strip adheres to the skin adjacent to the blister to maintain the pad in place. However, with many such conventional bandages, friction applied to the bandage by clothing or the like may be transferred to the surface of the blister, causing it to pop or to a wound, causing further damage to the wound.
Chaffing of the skin also may be caused by rubbing of clothing or footwear against the skin. Chaffing is a particular concern for runners, such as chaffing caused by clothing rubbing against the nipples which produces much discomfort.
Chaffing and blisters that result from frictional interaction between clothing or footwear and the skin may be prevented if such friction is reduced or prevented. Bandages have been proposed to prevent chaffing and the formation of blisters or other damage to the skin caused by such frictional forces. Conventional bandages used for this purpose typically are ineffectual, for the reasons discussed above, since the bandage itself will be caused to rub against the skin by the clothing or the footwear, and this rubbing also can cause blisters or other damage.
The ineffectiveness of conventional bandages for preventing chaffing, blisters or other injury or for protecting wounds or blisters is particularly acute with respect to blisters caused by ill-fitting footwear in which a portion of the footwear repeatedly rubs against the skin. This repeated rubbing produces and maintains the blister each time the footwear is worn. Such rubbing forces imposed on bandages, whether compressive or shear forces, often are transmitted to the inner protective layer of the bandage and to the underlying skin. Those forces either injure the area or, if it is injured already, prevent the area from properly healing.
Although bandages for preventing chaffing, protecting blisters and absorbing forces are known, there is a need for improved structures that are more effective in shielding an injured area of the skin and preventing injury. Examples of known bandages are disclosed in the following U.S. patents and published application: U.S. Pat. Nos. 2,992,644; 3,416,525; 3,927,669; 4,126,130; 4,561,435; 4,616,644; 4,671,266; 4,901,714; 5,170,781; 5,336,209; 5,954,679; 6,343,604; 6,384,294; and 2002/0128580.